BQM 419

    Keywords: Question
[Diagram]
Black to play  

AWA: This position arose in one of my DGS games (the game is still going on - [ext] http://www.dragongoserver.net/game.php?gid=410857). I played the marked move because I thought that any other move would turn out badly (or worse, in any case). I made this page to try to understand why this works if it does, and if it doesn't, how badly it fares against other moves.

Bob McGuigan: Since this is a game in progress, analysis of white+circle could affect game play so I'll just point out the usual joseki for the upper right corner:

[Diagram]
Joseki  


This is a good way for White to play because the three stones B3, B5, and B7 are somewhat heavy and may become a target for attack.

AWA: This part of the game has been played out, so it is safe to discuss now.

[Diagram]
Variation?  

AWA: This is how it went down from the point originally posted. 11 at B, 12 at W, 13 at #, 14 at @. Being only 5k (against a 1d opponent!), I probably made a mistake somewhere, since my global awareness is not very good.

xela: This seems to be the current position, so it's best not to analyse this diagram just yet. Going back to the beginning, though:

[Diagram]
Proverbial  

xela: The proverb says "crosscut-extend". I'm not sure what white would do next here.

JG: My first thought was to play directly at c. But it is clearer for White to begin with a. Then, if Black b, White c leaves White connected and Black split. Black should probably play c in response to a, but he still ends up split.

kokiri yeah, the crosscut-extend page alters the proverb to: When there are no other stones nearby, extending from the crosscut gives the advantage and I think that 1 is pretty unpleasant for black after white a.

[Diagram]
Continuation  

Dieter: the usual two stone sacrifice at B4 gives Black a forcing move at B5, but after B9 White can choose between a, preventing a Black sente (but crawling on the second line), b attacking the lone corner stone, or even c, attacking the shape of Black's alleged thickness, which may be an overplay. In any case this result is not good for Black.

[Diagram]
Basic instinct  

Dieter: In a crosscut situation, basic instinct is indeed to extend, but then the weaker stone. This is the first move to evaluate. I think in this case it is also the best move.

[Diagram]
Var 1  

In this variation, Black's hurting the marked white stone is much better than White's capturing the marked black stone. Black will end up with a big corner, White with a somewhat overconcentrated shape on the outside.

[Diagram]
Var 2  

Here, White sacrifices two stones, but his outward influence lacks a potential base and the attack on the corner stone is bound to backfire.

[Diagram]
Var 3  

A more difficult variation is this one. If B3-W4-B5 it looks like Black will come out best but I still have to calculate it. Someone?

kokiri - i was going to ask you about this, with W6 at a. When i have a little more time, i'll put up what i thought, but i certainly didn't come to any real answer. (I also wonder about B3 at 4).


BQM 419 last edited by Dieter on July 5, 2008 - 12:49
RecentChanges · StartingPoints · About
Edit page ·Search · Related · Page info · Latest diff
[Welcome to Sensei's Library!]
RecentChanges
StartingPoints
About
RandomPage
Search position
Page history
Latest page diff
Partner sites:
Go Teaching Ladder
Goproblems.com
Login / Prefs
Tools
Sensei's Library